/*

<This Java Class is part of the jMusic API version 1.5, March 2004.>

Copyright (C) 2000 Andrew Sorensen & Andrew Brown

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or any
later version.

This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

package jm.audio.io;

import jm.audio.AOException;
import jm.audio.AudioObject;
import jm.audio.Instrument;

import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.TargetDataLine;

/**
 * Real Time audio input
 *
 * @author Andrew Sorensen
 * @version 1.0, Sun Feb 25 18:42:41  2001
 */
public final class RTIn extends AudioObject {
    //----------------------------------------------
    // ATTRIBUTES
    //----------------------------------------------
    /**
     * have we reached the end of the audio file
     */
    public boolean finished = false;
    /**
     * the size of the holding buffer used by the TargetSource
     */
    private int bufsize;
    /**
     * the audio input data source
     */
    private TargetDataLine dline;
    /**
     * have we started running yet ?
     */
    private boolean started = false;

    //----------------------------------------------
    // Constructors
    //----------------------------------------------

    /**
     */
    public RTIn(Instrument inst, int sampleRate, int channels, int bufsize) {
        super(inst, sampleRate, "[RTIn]");
        this.sampleRate = sampleRate;
        this.channels = channels;
        this.bufsize = bufsize;
        this.init();
    }

    //----------------------------------------------
    // Public methods
    //----------------------------------------------

    /**
     * @param input bogus input here to fit in.
     */
    public int work(float[] buffer) throws AOException {
        if (!started) {
            this.dline.start();
            started = true;
        }
        int ret = 0;
        int bc = 0; //byte counter
        int amount = buffer.length * 2;
        byte[] data = new byte[amount];
        dline.read(data, 0, amount);
        for (; ret < buffer.length; ret++) {
            short input = (short) ((data[bc++] << 8) + (data[bc++]));
            buffer[ret] = (float) ((float) input /
                    (float) Short.MAX_VALUE);
        }
        return ret;
    }

    public void init() {
        AudioFormat af = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED
                , (float) this.sampleRate, 16, this.channels, this.channels * 2, this.sampleRate, true);
        DataLine.Info info = new DataLine.Info(TargetDataLine.class, af);
        System.out.println("Setting for audio line: " + info);
        if (!AudioSystem.isLineSupported(info)) {
            System.out.println(info);
            System.err.println("JMF Line not supported ... exiting .. sothere");
            System.exit(1);
        }
        try {
            this.dline = (TargetDataLine) AudioSystem.getLine(info);
            //multiply buffersize by 2 because this is bytes not shorts
            this.dline.open(af, bufsize * 2);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
